The subject matter disclosed herein relates to compressors and, more particularly, to scroll compressors with removable hydropads.
Scroll compressors are one type of a compressor that is commonly used in vapor cycle refrigeration systems (VCS) and typically use a scroll set to pump refrigerant. The scroll set can include a fixed scroll and an orbiting scroll. During compressor operation pressure in the orbiting scroll pockets tends to push the orbiting scroll against a hydropad surface. However, since the hydropad often contains seals that constrain refrigerant gas, the orbiting scroll is able to “ride” on a cushion of high pressure refrigerant gas in the hydropad cavity. That is, the high pressure refrigerant gas supports the orbiting scroll and prevents the orbiting scroll from actually coming in contact with the hydropad surface.
During compressor start-up and shutdown operations, the volume of the high pressure refrigerant gas drops and the orbiting scroll tends to touch down on the hydropad surface as a result. Over years of compressor in-service operations, some units that are returned for overhaul and repair have been found to exhibit excessive wear of the hydropad surface and/or excessive wear of the hydropad seal glands. Thus, since the hydropad is typically an integral part of a motor housing which are usually one-piece designs, the damage to the hydropad surface or seal glands cannot be repaired and necessitates time consuming and costly replacement of the entire motor housing.